Here’s a handy little tip. I’m pretty sure I heard it first from Mr. Jack Spirko:
Save the root ends of your green onions (aka scallions) — the parts you cut off when you’re cooking. Plant those, roots down, under about an inch of soil and they will generate new green onions. Keep this cycle going throughout your growing season and you should have an endless supply of green onions for your table. It’s much easier than starting from seed!
Green onions are shallow rooted, so work very well in pots. Also, they’re so unobtrusive and easy to grow that you can just tuck them here and there in your garden–anywhere that gets water–and forget about them until you need them.